1. Field of the Invention
The present invention relates to an image fluctuation correcting apparatus configured to rotate some of apex angle prisms along a plane nearly perpendicular to an optical axis of image lenses in a fame body arranged on the optical axis of image lenses by means of electromagnetic force according to an amount of fluctuation of a captured image, and cancel the amount of fluctuation to correct image fluctuation.
2. Description of the Related Art
An optical type fluctuation correcting apparatus (image fluctuation correcting apparatus) is conventionally applied to a video camera, an electronic still camera, a still camera or the like. The optical type fluctuation correcting apparatus optically corrects an amount of fluctuation of a captured image, which occurs due to vibration by capturing, in order to capture an image as an easily viewable image without the fluctuation of subject image.
Japanese Patent Laid-open Publication H06 (1994)-281889 discloses one example of the optical type fluctuation correcting apparatus. This optical type fluctuation correcting apparatus is provided with a pair of a concave lens and a convex lens mounted in a video camera. At least one of the concave lens and the convex lens is controlled in a direction for canceling an amount of fluctuation of a captured image. The optical type fluctuation correcting apparatus is configured to rotate at least one of the concave lens and the convex lens around a center of hypothetical curvature according to the amount of fluctuation and cause luminous flux to polarize.
Japanese Patent Laid-open Publication H10 (1998)-104678 discloses another example of the optical type fluctuation correcting apparatus. This optical type fluctuation correcting apparatus is provided with a first apex angle variable prism which is formed by a plano-concave lens and a plano-convex lens and configured to rotate in a perpendicular direction thereof, and a second apex angle variable prism which is formed by a plano-concave lens and a plano-convex lens and configured to rotate in a horizontal direction thereof. The optical type fluctuation correcting apparatus is capable of two-dimensionally varying a transmissive optical axis by rotating the first and second apex angle variable prisms according to an amount of fluctuation and composing rotation angles of the first and second apex angle variable prisms.
The optical type fluctuation correcting apparatus disclosed in Japanese Patent Laid-open Publication H06 (1994)-281889 can rotate at least one of the concave lens and the convex lens around a center of hypothetical curvature according to the amount of fluctuation and cause luminous flux to polarize. However, if this optical type fluctuation correcting apparatus rotates the convex lens by using a convex lens rotation means, the configuration of convex lens rotation means becomes complex and large in size because the convex lens rotation means is composed of a pair of upper and lower convex lens support members that support the convex lens, a pair of left and right convex lens perpendicular rotation members that respectively rotate the pair of upper and lower convex lens support members in a perpendicular direction thereof, a convex lens horizontal rotation member that is mounted between the pair of left and right convex lens perpendicular rotation members and rotates the pair of left and right convex lens perpendicular rotation members in a horizontal direction thereof, an electromagnetic means for perpendicularly rotating the convex lens and an electromagnetic means for horizontally rotating the convex lens. Therefore, it is difficult to downsize the optical type fluctuation correcting apparatus because it needs space for installing these constructional members.
The optical type fluctuation correcting apparatus disclosed in Japanese Patent Laid-open Publication H10 (1998)-104678 can two-dimensionally vary a transmissive optical axis by rotating the first and second apex angle variable prisms according to an amount of fluctuation and composing rotation angles of the first and second apex angle variable prisms. However, if this optical type fluctuation correcting apparatus rotates the first and second apex angle variable prisms by using a lens rotation means, the configuration of lens rotation means becomes large in size because the lens rotation means causes a pinion mounted on an axis of motor to mesh with a rack mounted on a side wall side of each apex angle variable prism. Therefore, it is difficult to downsize the optical type fluctuation correcting apparatus because it needs space for installing these constructional members.